During a discussion in person, it was identified that Coverage doesn't
currently work for ARM yet. Also, there are a number of errors with the
existing coverage document.
Take the opportunity to rewrite it in RST, making it easier to follow for a
non-expert user.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>